The Generation of the Dispersion wished to receive
sustenance from on High without curbing their egos and desires. Their plan was
to elicit sustenance from the Name Havayah, although they deserved no
better than to receive sustenance from the lowest levels of the Name Elokim.
They desired to reach beyond the law-and-order world of Tikun to the
world of Akudim, where the structure of Tikun does not exist. This
verse can thus be interpreted as follows:

"Let us make ourselves a name": Let us draw from
the Name Havayah.

"so that we will not be scattered": Lest we receive
from the lowest levels of the Name Elokim.

To achieve this unity, they planned to build a tower.

To achieve this unity, they planned to build a tower.
As the medieval commentator, Rabbi AvrahamIbn Ezra explains, they were
shepherds who often roamed far from one another. This tall tower would be
visible to them all from afar, so they would be able to return to it to regroup
and reunite.

G‑d therefore could not allow their plan to succeed,
since through unity they indeed would have been able to elicit Divine
beneficence from the Name Havayah and channel it into impurity.
(Similarly, once Adam had internalized evil by eating from the Tree of
Knowledge, G‑d did not want him to eat from the Tree of Life and gain
immortality, thereby eternalizing evil.)

The sin of this generation caused the Divine Presence
to retreat from the fourth firmament to the fifth.